Pretty in Red - Colour and the Spectrochemical Series

The high spin d-electron configurations for d -d10 systems, with examples of aqua metal ions of these configurations, and their colours. (Although not shown in the figure, A0 varies across the group of ions selected as examples.) 

The electronic spectra of (at left) a tetrahedral versus an octahedral complex, and (at right) the shift in the spectrum of an octahedral complex on replacement of just one donor group by another with a different position in the spectrochemical series. 

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